Duplex sewing machine



D. W. KLAU DUPLEX SEWING MACHINE Filed Dec.v 5, 1925 4 Sheer.s-Shee%l l Nov. 3o 192e.

Nov. 30 1926.

` D. W. KLAU DUPLEX sEw-ING MACHINE Filed Dec. 5. 1925 4 Sheets--Sheet 2 Arm/wier i Nov. 30 1926.

D. W. KLAU DUPLEX SEWING MACHINE Filed Dec. 5. 1925 4 Sheets-Sheek 3 Nov. 30 1926.

D. W. KLAU DUPLEX SEWING MACHINE 4 Sheets-Sheet 4 Filed Dec-*5. 1925 ATTORNEY Patented Nov. 30, 1926.

vPATENT O FFICE.--

DAVID W. KLAU, F NEW YORK, N. .'Y.

DUPLEX SEWING MACHINE.

Application led December This invention relates to duplex sewing machines for making two parallel lines ofi stitching simultaneously, particularly for sewing at one time the two side hems o f a strip of roller-shade material. The .oblect of the invention is to provide certaintimproved features for facilitating the ad]ust ment of the machine and the doing of the work. v

In the accompanying drawings forming a part hereof:

Fig. 1 isa front elevation o f a machine embodying the features of the invention;

Fig. 2 is a plan view showing the 4material, an intermediatepoition o f the strip being hemmed being broken out 1n order to showthe parts of the machine beneath;

Fig. 3 is a vertical section, on a larger scale, taken on the line of Fig.- 2;

Fig. 4 is a vertical section taken on the v line 4 4 of Fig. 2, looking from the rear, as indicated by the arrows, a portion of the framework at one end being broken out to -show `a rack;

Fig. 5 is a fragmentary vertical sectional elevation on an enlarged scale, taken in the same plane as Fig. 4 but looking from. the front'at one of the ting devices; g Fig. 6 is a section taken at right angles to Fig. 5, showing the same parts;

Fig. 7 is a section taken on the line 7-T` of Fig. 5, showing the thread-holder and cutter in actuated-position; and D Fig. S is a fragmentary front elevation showing a bracket secured to the loottomrof'A the right-hand `machine of Fig. l l

Themachine has av flat-top table .or support l2, supported on y'suitable uprights `3.

,40 The table is constructed so as to have awidc p an opening through j the top. VThis slot vor opening advantageously formed between transverse beam 'members 5.' In the upper in'ner edges transverse slot 4 f-forming' of these-table "members" are rabbeted ways 6, on which the bases 7 and 7 a of two sewing" :machines 8 and 8a? are supported. Said m`a` vchines are'laterally spaced toward opposit-e endspf-the slot 4 Iof `the-table, `and arei'e-v 59 versed sothat the'heads 9,9oithe'mach1nes Jare opposed to-each'other.

The' twoffsewing machines aredriven in unison? from ^`Y transverse? vshaft-s 5 10 and 1'0* thread-holding and cut.

5, 1925. Serial No. 73,311.

machines and are geared together` so as to rotate in opposite directions by meshing ears 12 on their proximate ends. The drive rom the opposite revolving shafts to the sewing machines consists of sprocket wheels 13 and 13 on the shafts, with sprocket chains 14, 14a passing over these wheels and over other sprocket wheels 15, 15a on the sewing machines, the chains passing through the slotted opening 4.

One or both 'of the sewing machines are relatively movable to vary the spacing bea all shade strips regardless of variations iny width. The base 7 of this machine is'freely` slidable on* the ways 6 and special lmechanism is provided enabling the operator "sit ting at the front :of the: tabev to adjust the position of the machine quickly and'faccu'-A rately without leaving her place.y Abracket f yThe bracket^165is`also inade'with abgear-if This shaft is disposedatfiight angles 1t`o"`l ways -G, and ek'tendsiforward beneath heY table tothe front, where itislprovided,

travels with the 1na',chineE 'when,theIftter isfshifted, and' th'ebeam members 5 arelongi-l tudinallv slotted at y24 to permit the passage of the shaft .i and* its.` .translational movement.

drive the sewing machine kalong theJ ways in one direction or the other, dependmg upon 4the direction in which the hand-wheel is turned.- The location of the pinions at opposite sides of the bearing 21 insures an even application of pressure to shift the' sewing machine.

Means are also associated with the shaft 22 andv hand-wheel 23 to enable the sewing machine 8 to be clamped or locked at its various positions. A collar 27 fixed to the shaft at the inner side of the front beam 5 and provided with a washer 28 constitutes one clamp element adapted to be forced a 'ainst this clamping abutment face. AThe andwheel. 23 is connected t'o the Youter end of the shaft in a manner indicated at 29 so as to permit 4it to have slight longitudinal movement thereon, and this movability is utilized to apply clamping pressure through v a spacer tube 30 to the abutment face of a slotted cover plate 31 which is applied to the outer side of said beam, covering the recess therein. A wing-nut 32 engages screwthreads 33 on the outer end of the shaft, and

constitutes an embodiment of an actuating device adjacent the hand-wheel to react 'between the concentric members so as to draw outward on the inner part and press inward on the outer'part, thus applyin the clamping elements to the abutment. aces. A turn of the nut 32 in the unscrewing direction releases the lock, whereupon turning of the hand-wheel shifts the sewing machine 8.

The precise positioning of the machine is thereby quickly and easily obtained, and the operator then tightens the nut 32 to lock the position.

The mechanism for driving'l the two sewing-machines which' has been described has the advantage of simplicity, and permits two ordinary sewing machines to be used, with an inexpensive change in one of them to reverse its feed, so that in the reversed position of the machine it will feed in the same dirction as' the other machine. The positive drive compels the two machines to operate in exact unisonyand they can be disconnected from each other' for re-threading and re-timed very readily by tilting the machine 8a so as to free the sprocket chain 14a. Before re-applying the chain', the sprocket wheel 15a of this sewing machinefis turned to the proper point so that when the chain is put on again the two machines will be in the same phase. 1

The strips of shade fabric come to the operator rolled up andwith their side hems folded but not sewed. Heretofore it has been customary for the operator to hold the roll in her lap while she unrolls and sews it. A feature of the-,present invention is the provision of an adjustable roll-holder on the front of the table. j This holder preferably comprises two curved metal straps 34, 34

, presser-foot.

or formed with, a long, variously bent bracket 36, which is screwed to the under side of the base 7 of the sewing machine 8 thence extending forward in a circuitous manner to avoid parts beneath vthe table, and at the front of the table being curved to form the member 34. Consequently, when the machine 8 is shifted to vary the spacing between the two machines, the roll-holder is likewise automatically adjusted.

The adjustable holder member 34 is braced by a supporting bar 70, which extends transversely beneath the forward portion of the bracket, the ends of this bar being secured to the under side of the table. The bracket rests upon this support and slides along the same when the holder member 34 is shifted to right or left.

Still another feature of the invention relates to thread-.cutting and holdin devices, which materially simplify the duties of the operator of this duplex machine; and means are provided whereby these devices are relatively adjustable with the adjustment between the sewing machines.

In the particular construction illust-rated, the table is formed with a narrow slot 3T parallel with and behind the slot Iopening 4. In this slot are fixed metal bars 38, 39- separated by a thin slot 40. In this way, aislotted guide is formed, and the upper front corner edge of the guide slot constitutes a stationary shearelement.

lThe movable thread-holding and cutting` devices are marked 41, 41, and since they 'are o1" may be of duplicate construction, the

same reference characters will beapplied to tageously formed integral with the plate 42 and in the same plane therewith, so as to enter the slot 4() and coact with` the stationary cutting edge at the front thereof.

The presser-foot 44 lies infront of the blade 43, has a friction pad 45 on its under side, and is vertically movable relatively to the plate and blade. For .this purpose a horizontal flange 46 is provided on the plate at the top of the blade projection, this flange being perforated with holes to receive headed studs 47, which project upward `from the Coil springs 48 about these studs exert 4pressure between the presserllt) foot and the lange`46 so as to hold the presser-foot thrust downward relatively to the plate and knife.` When-the blade enters the slotto out the thread, the presserfoot bears under spring-pressure upon the top of the table, gripping the thread.

The lower portions of the plates 42, below the guide slot 40, are connected, or in operative relation, `to suitable operating means. An advantageous embodiment of such means is one including a transverse, vertically movable rod 49, on remote portions of `which the lower ends of both the plates 42 are mounted, the said ends being formed with collars or bearings 50 for the purpose. At an intermediate point the horizontal rod has connected to it the upper end of a pull connection 51 extending downward to a pedal 52. ,The rod has slabbed portion; 53 at suitable points, which are guided in guides 54 projecting jdownward beneath the table. The-upward and downward movements ofthe rod are limited by stops 55, 56, and springs 57, 58, 59) disposed Vat appropriate points serveto hold the rod in its upper position, with the thread-cutters and holders raised above the table top.

The plate 42 of the device 4l, which lies behind the head of the sewing machine' 8, is shiftable along the rod^49, and lengthwise of the slot 40. This movement is effected in alverysimple and direct manner by a finger 60 vwhich is screwed to the top of the base of tlies'ewing machine 8 and projects rearward therefrom into a vertical slot in the plate 42; In this way, the thread-holder and cutter is connected with theshiftable machine, so as to be shifted'iequally there- V the, sewing-machine.,` y y Another pedal 61has a connection'62 "er-V with, yet said devicepremains at all times in operative relation to its-operating means, as the rod 49, and it is at all tnnes free ,for up and down movement notwithstanding its shifter connection with the frame of" tending upward to a-fcontrol-box '63v for starting and stop ing the sewingmachines. The shaft 10a is riven from this box by a belt 64 passing over pulleys. The source of power, preferably an electric motor, does not require illustration.

The slot opening 4 between the machines 8 and 8a is closed, or approximately closed, by a suitable number of removable plates 65 with which the operator is provided, the

plates resting on the guides 6.

What-is claimed as new is:

1. In a machine of the character described, a table having ways, a sewing machine slidably mounted thereon, said table having an under portion providing clamp abutment faces extending parallel with said ways, mechanism for shifting the sewing machine along the ways having an operat- .ing shaft journaled in a bearing carried by the sewingmachinmsaidl shaft extending at right angles to said ways and abutment faces and provided with a hand-wheel,

clamping means on the shaft comprising two portions adapted to be forced in opposite directions to apply clamping pressure against said abutment faces, and an actuating device on the forward end of said shaft adjacent the hand-wheel to react between said portions of the clamping means.

2. In a double-hemmmg machine, the combination with a table, andtwolaterally spaced sewing machines mounted on said table so as to be relatively movable toward and from each other, of a roll-holder at the front ofthe table, said roll-holder compr-ising two relatively movable portions, and means whereby said portions are relatively shifted automatically' withv the relative movement between the sewing machines.

3. In a double-hemming machine,the combination with a table, and two sewing :machines mounted in laterally s aced relation thereon, one-cf said machines; eingmovable on ways to vary the spacinghetween themachines, of ra roll-holder at the lfront.' ofk the table comprising two relatively movable members, and a bracket arm secured toand movable with said movable sewing machine.

movable withsaid movable sewing machine r i and extending forwardlyl beneath-the table and carrying one 'of the roll-holdei` members,

and a transversesupportion the `table'for the forward part of said bracket arm;

k5. In a double-hemming machine, the lcombination' withI a'table, and two laterally spaced' sewing.'fmachinesH mounted onl said table so as to be relatively movable toward and from each other, of a pair of threadholding and cutting devices over the table behind said sewing machines, with joint operating means beneath the table for depressing said devices to hold and cut the threads, said table containing means to cooperate with said devices, a'nd means whereby said devices are relatively shifted automatically with the relative movement between the sewing machines.

6. The combination` with a table, and a sewing machine shiftable laterally thereon, of a thread-holding and cutting device likewise movable over the table back of the sewing-machine, the table being adapted to cooperate therewith, means beneath the table for operating said device, a connection between said device and the frame of said sew- 8. The combination with a table, and a I sewing machine shiftable laterally thereon,

of a thread-holding and cutting `device overthe table back of saidsewing machine, said device being supported independently of said sewing machine and being similarly shiftable, means beneathv the table for operating" said device, and a connection from theframe of said sewing machine for .shifting said device.

9. In a double-hemming machine comprising a table and two laterally spaced sewing machines, one of said sewing machines being movable'laterally to vary the spacingbetween the machines, a pair of thread-holding and cutting devices behind said machines, a transverse vertically movable rod and means for operating the same to actuate both said devices, and a connection whereby one of said devices is shifted along said rod' with the shifting of thecorresponding sewing machine.

10. The combination with a support, andv a sewing machine shiftable thereon, of a thread-holding and cutting device behind said machine, a horizontal vertically movable' rod along which said device is shiftable, and means for depressing said rod.'

11. The combination with a support and a sewing machine shiftable thereon, of' a thread-holding and cutting device behind said machine, a horizontal vertically movable a sewing machine shiftable thereon, of a.

thread-holding and cutting device behind said machine, a horizontal vertically movable rodalong which Said device is shittable, a horizontally extended lguide and cutting edge, and means for operating said rod.

13. I n a doble-hemmin'g machine comprisng a table and two laterally spaced sewing-machines thereon, a slotted guide in the table behind said sewing-machines, a pair of standards passing vertically through said guide, cutting blades and presser-feet carried in laterally and inwardly overhanging relation by said standards, and pedal-operated means connected with the lower parts of both standards for depressing the same.

14. In a double-hemming machine comprising a tableY and two laterally spaced sewing-machines thereon, a slotted guide in the table behind Said sewing-machines, a pair of standards passing vertically through said guide, cuttingblades and presser-feet carried in laterally and inwardly overhanging relation by said standards, a transverse rod beneath the table to which the lower portions of both standards are connected, means for depressing said rod, and means for normally holding said rod and standards in the upper position.

15. In a double-hemining machine cornprising a table and two laterally spaced winfr-machines thereon, a slotted guide in the table behind saidsewing-machines, a pair of standards passing vertically through said guide, cutting blades and resser-feet carried in laterally and inwar ly overhanging relation by said standards, and a transverse vertically movable operating rod tovwhich the lower portions of both said standards are operatively related.

DAVID w. KLAU. 

